Gore earned $6.45 million last season, but the 49ers aren't about to pay that kind of money long-term for a 31-year-old runner. Still, his importance to San Francisco's offense rivals that of Marshawn Lynch in Seattle. New coach Jim Tomsula wants to pound the ball, but there's no guarantee that second-year back Carlos Hyde can step into Gore's shoes after just 83 carries as a rookie.

If Gore winds up elsewhere, one potential landing spot might be Buffalo. Depending on how Gore feels about reuniting with former Niners play-caller Greg Roman, the Bills could use help in the backfield if C.J. Spiller departs. Roman, though, also has a history with Anthony Dixon and might be inclined to hand a larger role to Bryce Brown.